1. Field of the Invention
The present invention relates to a liquid jet head and a liquid jet apparatus.
2. Description of Related Art
A piezoelectric element used for an ink jet printing head as a representative example of a liquid jet head ejecting liquid droplets has a problem that the piezoelectric element is easily broken down due to an outside environment such as humidity. In order to solve this problem, a piezoelectric element in which the outer circumferential surface of a piezoelectric layer is covered with an upper electrode is disclosed in JP-A-2005-88441, for example. However, the piezoelectric layer can be prevented from being broken down due to humidity by covering the piezoelectric layer with the upper electrode. However, since the upper electrode formed on the end surface of the piezoelectric layer is very close to a lower electrode, a problem may occur in that dielectric breakdown occurs between both the electrodes and thus the piezoelectric element is broken down.